With well over 100 million copies of his books sold worldwide and countless adaptations, ranging from films to video games, Cha was universally regarded as the most influential Chinese novelist of the 20th century. Cha also co-founded the Hong Kong newspaper Ming Pao Daily News.

Beijing’s liaison office in the city said in a statement on Friday night that 13 current and former state leaders of China, including President Xi Jinping, Premier Li Keqiang and Han, had mourned the passing of Cha. But the office only published Han’s letter of condolence to Cha’s family on Sunday.

In the letter, Han said: “Mr Cha was a famous writer and an outstanding newspaperman. He spent his life safeguarding and promoting Chinese traditional culture.”

“With great skill, he wrote of his feelings towards the country. He was prolific and achieved extraordinary things,” he added.

Han also described Cha as a loyal and noble patriot who “loved his country, loved Hong Kong, and supported the one country, two systems principle”.

In a reference to Hong Kong’s mini-constitution and the 1997 handover, the vice-premier said: “Cha contributed his energy and wisdom to the drafting of the Basic Law and the establishment of the Hong Kong special administrative region.”

The State Council’s Hong Kong and Macau Affairs Office also wrote a letter to Cha’s family on Friday, praising the writer as a patriot who “carried morality and justice on his shoulders and created masterpieces with his magic hands”.

Cha’s funeral is expected to be private, and details of it have not been disclosed.

Books of condolences will be opened at the Hong Kong Heritage Museum’s Jin Yong Gallery in Sha Tin for the public to pay tribute to the novelist from November 12 to 30.